Neue Borate der Alkalimetalle: KLi2[BO3]

New Borates of the Alkali Metals: KLi₂[BO₃] The hitherto unknown KLi₂[BO₃] is prepared in the shape of orthorhombic, colour-less-transparent, and columnar single crystals [a = 797.1(4) pm, b = 643.2(3) pm, c = 645.7(3) pm, Z = 4, d_x = 2.25 g/cm³, d_pyk = 2.20g/cm³]. The crystal structure was solved by four-cycle-diffractometer [PW 1100, MoKα, R = 5.78%, R_W = 3.83%, 452 I₀(hkl)]. Kli₂[BO₃] is sensitiv against atmospheric moisture which causes hydrolysis. Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated and discussed.     

Neue Borate der Alkalimetalle: KNa2[BO3]

New Borates of Alkali Metals: KNa₂[BO₃] We prepared hittherto unknown KNa₂[BO₃] in the shape of orthorhombic, colourlesstransparent and columnar single crystals [a = 603.9(2) pm, b = 560.2(3) pm, c = 556.8(2) pm, Z = 2, d_x = 2.54 g/cm³, d_pyk = 2.50 g/cm³]. The crystal structure was solved by four-cycle-diffractometer [PW 1100, MoKα , R = 3.73%, R_w = 2.88%, 386 I₀(hkl)]. KNa₂[BO₃] is very sensitiv against atmospheric moisture, and hydrolysis takes place. Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, and the Madelung-Part of Lattice Energy, MAPLE, are calculated and discussed.     

Neue Borate der Alkalimetalle: CsLi5[BO3]2

New Borates of Alkali Metals: CsLi₅[BO₃]₂ We prepared hitherto unknown CsLi₅[BO₃]₂ in the shape of monoclinic, colourless-transparent and columnar single crystals [a = 1179.5(2) pm, b = 943.3(2) pm, c = 809.6(3) pm, β = 132.76(8)°, Z ° 4, d_x = 2.859 g/cm³, d_pyk = 2,80 g/cm³].The crystal structure was solved by four-circle-diffractometer [PW 1100, AgKα, R = 5.7%, R_w = 3.8% für 1317 I₀(hkl)]. CsLi₅[BO₃]₂ is sensitive against atmospheric moisture, and hydrolysis takes place. Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, and the Madelung Part of Lattice Energy, MAPLE, are calculated and discussed.     

Neue Oxozincate der Alkalimetalle: Rb2[ZnO2] und Cs2[ZnO2]

New Oxozineates of Alkali Metals: Rb₂[ZnO₂] and Cs₂[ZnO₂] Colorless single crystals of the hitherto unknown Rb₂[ZnO₂] (a = 9.55₈, b = 6.33₅, c = 15.91 Å, β = 118.6°, z = 8, d_pyk = 4.11, d_rö = 4.21 g · cm^?3) and Cs₂[ZnO₂] (a = 9.85₁, b = 6.61₉, c = 16.26 Å, β = 116.8°) have been prepared, which crystallize monoclinic, P2₁/c – D. (For parameters see text.) Unexpected there are “isolated” groups [Zn₄O₈]. Half of the Zn atoms exhibit the unusual coordination number 3 towards O^2?. The Madelung Part of Lattice Energy, MAPLE, and the Effective Coordination Number, ECoN, the latter by means of Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Quaternäre Monoborate der Alkalimetalle: Na4Li5[BO3]3

Quaternary Monoborates of Alkali Metals: Na₄Li₅[BO₃]₃ We prepared hitherto unknown Na₄Li₅[BO₃]₃ in the shape of monoclinic, colourless-transparent and prismatic single crystals [a = 1238.8(5) pm, b = 729.6(3) pm, c = 973.8(3) pm, β = 107,29(4)°, Z = 4, d_x = 2,397 g/cm³, d_pyk = 2,37 g/cm³]. The crystal structure was solved by four-circle-diffractometer [PW 1100, MoKα , R = 9,02%, R_w = 5,29%, 1221 I₀(hkl)]I₀(hkl)]. Na₄Li₅[BO₃]₃ is sensitive against atmospheric moisture; hydrolysis takes place within 60 minutes. Effective Coordination numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, and the Madelung Part of Lattice Energy, MAPLE, are calculated and discussed.     

Zur Kenntnis der Oxoberyllate der Alkalimetalle [1, 2]

On Oxoberyllates of the Alkali-Metals The existence of the phases K₂Be₂O₃ (2 forms), K₄BeO₃, Rb₂Be₃O₄, Rb₂Be₂O₃,Rb₄BeO₃, Cs₂Be₃O₄ and Cs₂BeO₂ is proved by powder-datas according to GUINIER -SIMON . In single crystal form we obtained Li₄BeO₃ [a = 5.49; b = 9.53; c = 4.93 Å; a = 114.₁; ß = 105.₀; γ = 106.₆°; triclinic], Na₂Be₂O₃ [;a = 6.32; b = 8.53; c = 2.71 Å; α = 107.₇; ß = 105.₅; γ = 78.₄°; triclinic], Na₆Be₂O₅ [a = 5.67₂; c = 10.2₁ Å; tetragonal] as also K₂BeO₂ [a = 7.09₈; b = 10.57₇; c = 5.70₆ Å; γ = 131.₃°; monoclinic] and Rb₂BeO₂ [a = 7.46₃; b = 11.17₀; c = 5.88₁ Å; γ = 131.₈°; monoclinic].     

Zur Kenntnis der Oxopalladate der Alkalimetalle [1]

On Oxopalladates of Alkali Metals According to X-ray data of single crystals there are: Na₂PdO₂ (yellow rod-shaped crystals) orthorhombic, a = 3.07₇, b = 10.35₉, c = 8.35₁ Å, Z = 4; d_x = 4.60, d_pyk = 4.6₃ g · cm^?3. ?K₂PdO₃”? (black square prism) orthorhombic, a = 6.20₂, b = 9.21₉, c = 4× 11.37₂ = 45.4₈ Å, Z = 24, d_x = 3.60, d_pyk = 3.5₀ g · cm^?3, and ?K₆PdO₄”? (orange square prism) orthorhombic (pseudotetragonal), a = b = 12.36₈, c = 13.59₃ Å, Z = 8, D₂⁴—P2₁2₁2₁. ?Rb₂PdO₃”? (black) is isostructural (Guinier data) to ?K₂PdO₃”?, a = 7.35₄, b = 9.60₅, c = 11.58₆ Å, d_x = 4.58, d_pyk = 4.4₇ g · cm^?3. Na₂PdO₃ exists in another reddish brown form, isostructural to Li₂MnO₃ (C_2h⁶—C2/c), a = 5.37₄, b = 9.30₉, c = 10.78₉ Å, β = 99.5°, Z = 8, d_x = 5.00, d_pyk = 4.7₃ g · cm^?3.     

Neue Alkalioxoarsenate(V): NaLi2[AsO4] — ein neuer Formeltyp [1]

New Alkali Oxoarsenates(V): NaLi₂[AsO₄] — A New Type of Formula [1] . By heating of well ground mixtures of the binary oxides As₂O₃, Na₂O, and Li₂O₂, molar ratio As:Na:Li = 1.0:1.0:2.0, in a well closed Ni tube (650°C, 21 d) colourless single crystals of NaLi₂[AsO₄] were obtained for the first time. The new orthoarsenate(V) crystallizes orthorhombic (space group P mn2₁-C, No. 31) with Z = 2. The structure determination showed that it is isostructural to β_II-Li₃[VO₄] and that means the Li₃[PO₄]-type. The lattice constants a = 702.9(2) pm, b = 520.5(1) pm, c = 505.4(2) pm were taken from Guinier-Simon powder data. The structure was determined by four-circle diffractometer data [Philips PW 1 100, AgKα , 679 independent out of 2 373 I_o(hkl), R = 3.03%, R_w = 2.29%; parameter see text]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Li2Eu3Br2[BO3]2: A New Europium(II) Halide Oxoborate with Yellow Luminescence

The europium(II) oxoborate Li₂Eu₃Br₂[BO₃]₂ featuring lithium and bromide ions was synthesized by the reaction of Eu₂O₃ with Li[BH₄] as lithium- and boron- as well as EuBr₃ as bromide-source at 750 °C for 24 h in silica-jacketed sealed niobium capsules. The yellow, air-stable and yellow fluorescent compound crystallizes in the trigonal space group R3 m (a = 1049.06(7) pm, c = 2993.1(3) pm, c/a = 2.853, Z = 12). The two crystallographically distinguishable Eu²⁺ cations show either an eightfold coordination as bicapped trigonal prism ([EuO₆Br₂]^12–) or a ninefold coordination as monocapped square antiprism ([EuO₅Br₄]^12–). All oxygen atoms stem from isolated triangular [BO₃]^3– anions and the Li⁺ cations reside in octahedral voids provided by both oxygen atoms and Br^– anions.     

Zwei Fluoridborate des Gadoliniums: Gd2F3[BO3] und Gd3F3[BO3]2

Two Fluoride Borates of Gadolinium: Gd₂F₃[BO₃] and Gd₃F₃[BO₃]₂ By flux‐supported solid‐state reaction of Gd₂O₃ and GdF₃ with B₂O₃ (flux: CsCl, molar ratio: 1 : 1 : 1 : 6, sealed tantalum capsule, 700 °C, 7 d) the new gadolinium fluoride borate Gd₂F₃[BO₃] (monoclinic, P2₁/c; a = 1637.2(1), b = 624.78(4), c = 838.04(6) pm, β = 93.341(8)°; V_m = 64.418(6) cm³/mol, Z = 8) was obtained as colourless, prismatic, face‐rich single crystals. The four crystallographically different Gd³⁺ cations (CN = 9) are all capped square‐antiprismatically surrounded by fluoride and oxide anions, in which the latter represent always components of isolated trigonal planar [BO₃]^3— anions. The six crystallographically independent F^— anions all reside in more or less planar coordination of three Gd³⁺ cations. Thus the constitution of Gd₂F₃[BO₃] can be described as a sequence of alternating layers each of the composition Gd[BO₃] and GdF₃ parallel (100), respectively. The crystal structures of Gd₂F₃[BO₃] and the shortly published Gd₃F₃[BO₃]₂ (monoclinic, C2/c; a = 1253.4(1), b = 623.7(1), c = 836.0(1) pm, β = 97.404(6)°; V_m = 97.571(9) cm³/mol, Z = 4) are compared with each other. Due to the structural analogies between these two gadolinium fluoride borates, a disorder model of the boron atoms frequently found for Gd₂F₃[BO₃] is able to be transferred to Gd₃F₃[BO₃]₂ as well.     

Neue Oxogallate der Alkalimetalle: Über K6[Ga2O6] und Rb6[Ga2O6], sowie Na3GaO3 und Cs6[Ga2O6]

New Oxogallates of Alkaline Metals: On K₆[Ga₂O₆] and Rb₆[Ga₂O₆] as well as Na₃GaO₃ and Cs₆[Ga₂O₆] Due to powder and single crystal data K₆[Ga₂O₆] a = 7.09₉; b = 11.11₆; c = 6.48₄ Å; ß = 101.6₆° and Rb₆[Ga₂O₆] a = 7.39₃; b = 11.47₅; c = 6.79₈ Å; ß = 103.5° crystallize isotypic with K₆[Fe₂O₆]; space group C2/m-C₃^2h; As well has been prepared the hitherto unknown Na₃GaO₃ a = 11.48, b = 10.82, c = 6.13 Å, space-group Imcm or I2cm Z = 8; and Cs₆[Ga₂O₆] a = 7.2₆, b = 12.1, c = 7.6₈ Å, ß = 105°, Z = 4, space-group P2₁/a.     

Neue Oxocadmate der Alkalimetalle: K6[CdO4],Rb6[CdO4], Rb2CdO2 und Rb2Cd2O3

The crystal structure of K₆[CdO₄] and Rb₂CdO₂ has been determined from single crystal X-ray diffraction data and refined toR=0.058 (K₆[CdO₄]) andR=0.088 (Rb₂CdO₂). K₆[CdO₄] crystallizes hexagonal, space group P6₃mc with lattice constantsa=867.42 (6),c=665.5 (1) pm,c/a=0.767 andZ=2. It is isotypic with Na₆[ZnO₄]. Rb₂CdO₂ is orthorhombic, space group Pbcn witha=1045.0 (2),b=629.1 (1),c=618.3 (1) pm,Z=4, and crystallizes with the K₂CdO₂ structure type. The crystal structures can be deduced from the motif of a closest packed arrangement of O^2– with hexagonal (K₆[CdO₄]) or cubic (Rb₂CdO₂) stacking. The tetrahedra occupied by Cd²⁺ are isolated (K₆[CdO₄]) or edge-shared (formation of infinite SiS₂-like chains [CdO_4/2]) (Rb₂CdO₂). The powder diffraction pattern of Rb₆[CdO₄] [a=906.6 (1),c=694.3 (1) pm] and Rb₂Cd₂O₃ [a=642.6 (2),b=679.0 (1),c=667.9 (2) pm, =115.2 (1)] confirm isotypie with K₆[CdO₄] and K₂Cd₂O₃ respectively.

Herrn Prof. Dr.Gutman zum 65. Geburtstag gewidmet.     

LaCl(BO2)2 und Er2Cl2[B2O5]: Zwei Chlorid‐Oxoborate dreiwertiger Lanthanide

LaCl(BO₂)₂ and Er₂Cl₂[B₂O₅]: Two Chloride Oxoborates of Trivalent Lanthanides Er₂Cl₂[B₂O₅] is obtained as single crystals by the reaction of ErCl₃, Er₂O₃ and B₂O₃ with an excess of ErCl₃ as flux in evacuated silica tubes after two weeks at 850 °C. The compound crystallizes as long, pale pink needles and appears to be air‐ and water‐resistant. Single‐crystalline LaCl(BO₂)₂ emerges from the reaction of La₂O₃, LaCl₃, and B₂O₃ with an excess of B₂O₃ as flux in evacuated silica tubes after four weeks at 900 °C. LaCl(BO₂)₂ crystallizes as thin, colourless, air‐ and water‐resistant needles which tend to severe twinning due to their fibrous habit. The crystal structure of Er₂Cl₂[B₂O₅] (orthorhombic, Pbam; a = 1489.65(9), b = 1004.80(6), c = 524.86(3) pm; Z = 4) contains two crystallographically different erbium cations. (Er1)³⁺ resides in pentagonal‐bipyramidal coordination of seven anions while (Er2)³⁺ is surrounded by only six anions with the shape of an octahedron. The planar oxodiborate units [B₂O₅]^4— consisting of two vertex‐shared [BO₃]^3— triangles are isolated according to {([BOO]₂)^4—}. LaCl(BO₂)₂ crystallizes isostructurally with PrCl(BO₂)₂ in the triclinic space group P1¯ (a = 423.52(4), b = 662.16(7), c = 819.33(8) pm; α = 82.081(8), β = 89.238(9), γ = 72.109(7)°; Z = 2). The characteristic unit consists of endless chains built up by corner‐linked [BO₃]^3— triangles. These quasi‐planar zigzag chains of the composition {[(B1)OO(B2)OO]^2—} (≡ {[BO₂]^—} run parallel [100]. The La³⁺ cations exhibit coordination numbers of ten and are coordinated by three Cl^— and seven O^2— anions.     

Neue Beryllate der Alkalimetalle: Na6Be8O11

Novel Beryllates of the Alkali Metals: Na₆Be₈O₁₁ For the first time transparent, colourless single crystals of Na₆Be₈O₁₁ have been prepared (Na₂O/BeO; Na:Be = 6:8, Ni-tube; 650°, 14 d). The compound crystallizes triclinic (P1 ) with a = 532.1(1) pm, b = 642.4(2) pm, c = 839.1(2) pm, α = 101.7°, γ = 105.8°, Z = 2, d_x = 2.42 g/cm³, d_pyk=2.51 g/cm³. The crystal structure was solved by four-circle diffractometer data [Siemens AED 2, MoKα , R = 7.9%, R_w = 6.2%, 1429 I₀(hkl)]. Effektive Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.     

Über Borati der Alkalimetalle. II. Zur Kenntnis von LiB3O5 [1]

On Borates of the Alkaline Metals. II. On the Knowledge of LiB₃O₅ Single crystals of LiB₃O₅ were obtained for the first time. LiB₃O₅ crystallizes orthorhombic in the space group Pn2₁a–C with the parameters a = 8.46₀; b = 5.13₃; c = 7.38₆. The structure was determined [404 reflections, MoKα, R = 3,6₅%, R_w = 3.3₁%]. LiB₃O₅ contains B₃O₅ groups, comparible to those in CsB₃O₅. Both compounds are not isotypic. Madelung Part of Lattice energy, MAPLE, is calculated and discussed.     

Zur Existenz polynärer Oxide der Alkalimetalle mit einwertigen Cobalt bzw. Nickel [1, 2]

On the Existence of Polynary Oxides of the Alkali Metals with Monovalent Cobalt and Nickel For the first time we obtained RbNa₂NiO₂, KNa₂NiO₂, Na₃CoO₂ and K₃CoO₂ [RbNa₂NiO₂: Na₂NiO₂ + Rb₂O, Rb:Ni = 1.8:1, 600°C, 28 d, Ni-tube; KNa₂NiO₂: Na₂NiO₂ + K₂O, K:Ni = 1.8:1, 600°C, 20 d, Ni-tube; Na₃CoO₂: Na₂O + CoO: Na:Co = 8.8:1, 500°C, 20 d, Co-tube; K₃CoO₂: K₂O + CoO: K:Co = 4.4:1, 550°C, 20 d, Co-tube]. According to X-ray structure analysis of single crystals monovalent Co and Ni is present [always four-circle-diffractometer data, MoKα -radiation; RbNa₂NiO₂: AED 2, all 163 I_o(hkl), R = 3.4%, R_w = 1.9%, I4/mmm, a = 461.7(1), c = 973.6(3) pm, Z = 2; KNa₂NiO₂: AED 2, all 341 I_o(hkl), R = 5.6%, R_w = 3.5%, Cmma, a = 1 048.5(3), b = 626.8(1), c = 621.9(1) pm, Z = 4; Na₃CoO₂: PW 1 100, 517 of 568 I_o(hkl), R = 2.9%, R_w = 1.8%, P4₂/mnm, a = 940.0, c = 464.5 pm, Z = 4; K₃CoO₂: PW 1 100, all 940 I_o(hkl), R = 5.0%, R_w = 3.9%, Pnma, a = 1 190.0, b = 730.4, c = 604.1 pm, Z = 4]. All samples are red, the single crystals transparent. Two O^2? coordinate Ni¹⁺ and Co¹⁺, respectively, like a dumb-bell. Mean Fictive Ionic Radii, MEFIR, and Effective Coordination Numbers, ECoN, and Madelung part of lattice energy, MAPLE, are given.     

Über Oxorhodate der Alkalimetalle: β-LiRhO2

On Oxorhodates of Alkali Metals: β-LiRhO₂ We prepared hitherto unknown β-LiRhO₂ in form of black, cubic single crystals, O⁴–F4₁32, a = 841.27(6) pm, Z = 16. For a first time in case of such metal oxides we find one of the possible variants of order between the NaCl-type with random distribution and the complete ordered types like α-NaFeO₂ as a single crystal (four-circle-diffractometer PW 1100, AgKα, 100 von 109 I₀(hkl), R = 9.10%, R_w = 5.46%). The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, were calculated and discussed.